We don't know. But President Bush says he has known Harriet Miers long enough that he feels sure.
For the rest of us, she is a stealth nominee. Not since The Invisible Man has there been so much stealth.
That's not ideal by a long shot. But ideal was probably never in the cards, given the weak sisters among the Republicans' Senate "majority."
There is another aspect of this. The Senate Democrats huffed and puffed when Judge John Roberts was nominated but, in the end, he faced them down and was confirmed by a very comfortable margin.
The Democrats cannot afford to huff and puff and then back down, or be beaten down, again. On the other hand, they cannot let a high-profile conservative get confirmed without putting up a dogfight to satisfy their left-wing special interest groups.
Perhaps that is why some Democrats seem to welcome this stealth nominee. Even if she turns out to vote consistently with Antonin Scalia and Clarence Thomas, the Democrats are off the hook with their base because they can always say that they had no idea and that she stonewalled them at the confirmation hearings.
The bottom line with any Supreme Court justice is how they vote on the issues before the High Court. It would be nice to have someone with ringing rhetoric and dazzling intellectual firepower. But the bottom line is how they vote. If the President is right about Harriet Miers, she may be the best choice he could make under the circumstances.